Rectangular square-opening valve

The utility model provides a rectangular square opening valve, which comprises a valve body, a valve plate, a rectangular square opening, an air cylinder, a valve cover, a transmission mechanism and a connecting port, the valve body of the valve body is respectively provided with a channel of the rectangular square opening and the connecting port, the connecting port is communicated with an external fluid supply device, and the top end of the valve body is provided with a first opening. The valve cover is arranged at the top end of the valve body and covers the first opening, a second opening is formed in the top end of the valve cover and communicates with the interior of the valve body, an air cylinder is arranged at the top end of the valve cover, and a transmission mechanism is arranged at the bottom end of the air cylinder and penetrates through the second opening to be arranged in the valve body. The valve plate is fixed to the transmission mechanism and can move up and down along with the transmission